Long term disease-free survival in acute leukemia patients recovering with increased gammadelta T cells after partially mismatched related donor bone marrow transplantation.

Allogeneic stem cell transplantation (ASCT) has improved leukemia-free survival (LFS) in many but not all patients with acute leukemia. This is an eight-year follow-up to our previous study showing a survival advantage to patients with an increased gammadelta T cells following ASCT. gammadelta T cell levels were collected prospectively in 153 patients (acute lymphoblastic leukemia (ALL) n = 77; acute myelogenous leukemia (AML) n = 76) undergoing partially mismatched related donor ASCT. Median age was 22 years (1-59), and 62% of the patients were in relapse at transplant. Patient-donor human leukocyte antigen (HLA) disparity of three antigens was 37% in the graft-versus-host disease (GvHD) and 29% in the rejection directions. All patients received a partially T cell-depleted graft using T10B9 (n = 46) or OKT3 (n = 107). Five years LFS and overall survival (OS) of patients with increased gammadelta compared to those with normal/decreased numbers were 54.4 vs 19.1%; P < 0.0003, and 70.8 vs 19.6% P < 0.0001, respectively, with no difference in GvHD (P = 0.96). In a Cox multivariate analysis, normal/decreased gammadelta (hazard ratio (HR) 4.26, P = 0.0002) and sex mismatch (HR 1.45 P=0.049) were associated with inferior LFS. In conclusion, gammadelta T cells may facilitate a graft-versus-leukemia (GvL) effect, without causing GvHD. Further evaluations of this effect may lead to specific immunotherapy for patients with refractory leukemia.

NHLBI plans for the promise of cell-based therapies.

This article presents the National Heart, Lung and Blood Institute (NHLBI) perspective on the status of cell-based therapies. A summary of current and future NHLBI/National Institutes of Health (NIH) programs is given along with a history of the development of NHLBI/NIH resources to aid the advancement of cell-based therapies. A brief discussion of clinical research programs to utilize cell-based therapies is also included.

Bone marrow transplantation from partially HLA-mismatched family donors for acute leukemia: single-center experience of 201 patients.

Between February 1993 and December 1999, 201 patients (1-59 years old, median 23) with acute leukemia (67% not in remission) underwent ex vivo T-cell-depleted (TCD) bone marrow transplants (BMT) from partially mismatched related donors (PMRD; 92% mismatched for 2-3 HLA A, B, DR antigens). Conditioning comprised total body irradiation, cyclophosphamide, cytarabine, etoposide, anti-thymocyte globulin (ATG), and methylprednisolone. Graft-versus-host disease (GVHD) prophylaxis comprised partial TCD with OKT3 (n=143) or T10B9 (n=58), steroids, ATG, and cyclosporine. The engraftment rate was 98%. The cumulative incidences of grades II-IV acute GVHD and chronic GVHD were 13 and 15%, respectively. The 5-year cumulative incidences of relapse and transplant-related mortality (TRM) were 31 and 51%, respectively. The actuarial 5-year overall survival (OS) and disease-free survival (DFS) probabilities were 19 and 18%, respectively. Patient age >15 years, active disease at transplant, donor age >25 years, and 3-antigen donor mismatch (host-versus-graft) affected the outcome adversely. The actuarial 5-year OS of four groups of patients identified based upon these risk factors was 39, 20, 13, and 0%, respectively (P<0.0001). We conclude that PMRD BMT is a potential treatment option for patients with high-risk acute leukemia who require an alternative donor transplant and fall into a group with a reasonable expected outcome.

Haploidentical vs autologous hematopoietic stem cell transplantation in patients with acute leukemia beyond first remission.

This is a retrospective comparison of partially mismatched related donor transplantation (PMRDT) and autotransplantation (ABMT) in advanced acute leukemia. Patients underwent T-cell-depleted PMRDT (n=164) or ABMT (n=131) for acute myeloid leukemia (n=130) or acute lymphoblastic leukemia (n=165). Fewer PMRDT patients were in remission (29 vs 85%; P<0.0001). The 5-year cumulative incidence of transplant-related mortality (TRM) was 52% after PMRDT and 16% after ABMT (P<0.0001). The 5-year cumulative incidence of relapse was 32% after PMRDT and 54% after ABMT (P=0.006). The actuarial unadjusted 5-year disease-free survival (DFS) was 16% after PMRDT and 30% after ABMT. In Cox's regression analysis, PMRDT (P<0.0001) and age >15 years (P=0.002) were associated with higher TRM, active disease (P=0.0021), ABMT (P=0.0074) and male sex (P=0.011) with higher relapse, and age >15 years (P=0.0007) and PMRDT (P=0.047) with lower DFS. Amongst second remission patients, TRM was higher after PMRDT (P=0.0003), relapse was higher after ABMT (P=0.034), and 5-year DFS was comparable (32% ABMT and 25% PMRDT). ABMT, if feasible, may be preferable to PMRDT in advanced acute leukemia patients since lower relapse after PMRDT is offset by higher TRM. If an autograft is not feasible because of nonavailability of autologous cells or very advanced disease, PMRDT is a potential alternative.

In vitro interactions between gamma deltaT cells, DC, and CD4+ T cells; implications for the immunotherapy of leukemia.

BACKGROUND: Gamma deltaT cells contribute to immune defense against infectious organisms and some malignancies, but the process of activation and proliferation of these cells is not well understood. It is known that the immune response of gamma deltaT cells is not MHC-dependent, but is likely based on direct recognition of surface peptides and non-peptide ligands. This study examined whether DCs and CD4(+) T cells can participate in the activation of gamma deltaT cells. METHOD: Peripheral blood gamma deltaT cells were co-cultured with CD34-derived autologous DCs and CD4(+) T cells using contact-dependent cultures and transwell systems. Proliferation, immunophenotyping, and cytotoxicity assays determined the extent of gamma deltaT cell proliferation and cytotoxicity. RESULTS: Human gamma deltaT cells expanded 221.3 +/- 76-fold in cultures with DCs, and 165.7 +/- 76.6-fold with CD4(+) T-cells alone. Proliferation was enhanced (1949.8 +/- 261.3-fold) when gamma deltaT cells were cultured with both DC and CD4(+) T cells. Proliferation was contact-dependent, and resulted in the expansion of V delta1+ or V delta2+ cells cytotoxic against several leukemic cell-lines, but not against allogeneic PHA-induced lymphoid blasts. Ligation of the T-cell receptor with anti-pan-delta Ab significantly up-regulated cytotoxicity against K562, KBM-5 and KG1a, and normal BM, but not against Molt-4, allogeneic EBV-transfected B cells and allogeneic PHA-blasts. Minimal cytotoxic activity was shown against allogeneic marrow colony-forming units granulocyte-macrophage and erythrocyte colony-forming units. CONCLUSION: DCs can participate in the activation of gamma deltaT cells against specific autologous targets, and cytotoxicity can be enhanced by further stimulation via the T-cell receptor.

Assessment of G-CSF stimulated BM hematopoietic stem cells in normal donors.

BACKGROUND: The clinical use of G-CSF has recently been expanded to include mobilization of stem cells for both autologous and allogeneic transplantation. Most of the published studies have focused on stem cells released into the peripheral blood (PB) after G-CSF treatment. However, little is known about the effects of G-CSF on BM. This study evaluated the concurrent effects of short-term G-CSF on both BM and PB stem and progenitor cells in normal individuals. METHODS: Volunteers received 5 or 10 microg/kg of G-CSF for 5 consecutive days (Days 1-5). On Days 0, 3, 6, 9 and 15, BM and PB samples were obtained. Flow cytometry and functional assay were performed to analyze stem cells, subpopulations, adhesion molecules, colony-forming units and LTCIC. RESULTS: The total nucleated cells and absolute numbers of CD34(+)/mL showed a similar response pattern in both BM and PB, with a peak around Day 6 that returned to baseline levels by Day 15. However, there was a reciprocal change in the percentage of CD34(+) cells between BM and PB compartments. The expressions of adhesion molecule showed an up- and down-regulation of alpha4 and alpha5 integrin subunits, respectively, also correlated with the CD34(+) mobilization patterns. DISCUSSIONS: The functional characterization of integrins, and further clinical examination of G-CSF-stimulated BM is warranted. G-CSF-stimulated BM maybe considered as an alternative source of stem cells in transplantation.

Allogeneic transplantation from HLA-matched sibling or partially HLA-mismatched related donors for primary refractory acute leukemia.

Allogeneic transplantation is successful in a minority of patients with primary refractory acute leukemia (PRAL). An HLA-matched sibling donor (MSD) is available only in 30-40% of the patients, whereas a partially mismatched related donor (PMRD) is available for most. We compared the outcome of 24 MSD (median age 24 years) and 19 PMRD (median age 34 years; P = 0.04) allograft recipients with PRAL. All MSD patients received non-T cell-depleted marrow whereas all PMRD patients received partially T cell-depleted marrow. All evaluable PMRD patients and 90% of the evaluable MSD patients attained CR. Six patients in each group with recurrent/persistent disease died. Ten PMRD (3-year probability 70%) and 14 MSD (3-year probability 63%) patients died of treatment-related causes. At the last follow-up, three PMRD (18-50 months; 3-year probability 14%) and four MSD (20-166 months; 3-year probability 20%) patients were alive and well. We conclude that allogeneic transplantation is a viable therapeutic option for PRAL. PMRD transplantation is a reasonable alternative in patients with no MSD, and results in similar outcome. In terms of identifying a donor and harvesting cells, a PMRD transplant is significantly quicker than an unrelated donor transplant - a point of great practical importance in the setting of failed induction chemotherapy where time is of the essence.

Colony-stimulating factors in stem cell transplantation: effect on quality of life.

Health-related quality of life (QOL) is poorest during the immediate post-transplantation period, but the impact of medical interventions during this period has not been studied. Colony-stimulating factors (CSFs), which are used to minimize short-term negative outcomes, might be expected to improve QOL; however, little is published about their impact on QOL during this period. We conducted a MEDLINE search to identify studies reporting on outcomes of stem cell transplantation (SCT) affected by the CSFs, mainly sargramostim and filgrastim. End points studied were: mucositis, incidence and type of infection, duration of hospitalization, time to myeloid engraftment, and quantity and quality of harvested cells. To impute the impact of CSFs on QOL post-SCT, we also reviewed the association between QOL and CSF outcomes in other circumstances. Data suggest that both CSFs improve QOL in the early autologous or allogeneic post-bone marrow transplantation period. Poor QOL caused by infection and increased length of hospital stay is expected to be improved by sargramostim. Time to myeloid engraftment, when negatively affecting QOL, is expected to be improved with both CSFs; however, the time to myeloid engraftment is consistently shorter with filgrastim. Current prospective trials designed to study the effects of CSFs in the immediate post-SCT period should collect QOL data.

Allogeneic bone marrow transplantation from partially mismatched related donors as therapy for primary induction failure acute myeloid leukemia.

The outcome of acute myeloid leukemia patients with primary refractoriness to conventional chemotherapy is extremely poor. Allogeneic bone marrow transplants with matched sibling or matched unrelated donors provide 10-20% disease-free survival in this setting. We analyzed our transplant experience using readily available partially mismatched related donor (PMRD) in patients with primary induction failure (PIF) AML. Between March 1994 and December 1998, 13 patients with PIF AML were transplanted from 0-3 HLA antigen mismatched donors. All 12 evaluable patients engrafted at a median of day +16. Ten (77%) patients survived at least 100 days after transplant. Acute GVHD (grade II) was observed in one of 12 patients. Chronic GVHD was seen in one of 10 patients surviving beyond day 100. The major cause of failure was relapse of disease in six occurring 3-12 months after PMRD BMT. Three patients are alive without disease 14, 36 and 45 months post BMT with Karnofsky scores of 100%. The actuarial 3-year probabilities of relapse and disease-free survival were 0.54 and 0.19, respectively. We concluded that a PMRD graft is a viable option, comparable to the use of matched related or unrelated donors, in patients with PIF AML in whom time is of the essence.

Human gammadelta(+) T lymphocytes have in vitro graft vs leukemia activity in the absence of an allogeneic response.

Refractory acute lymphoblastic leukemia (ALL) is often incurable, and relapse rates following allogeneic bone marrow transplantation (BMT) remain high. We have reported that patients who develop increased numbers of gammadelta(+) T cells soon after BMT are significantly less likely to relapse. We now show in seven donor/recipient pairs that donor-derived Vdelta1(+)CD4(-)CD8(-)gammadelta(+) T cells are activated and proliferate in response to recipient primary ALL blasts. In addition, these cells have been shown to bind and lyse the recipient ALL blasts. Separately, gammadelta(+) T cells proliferate poorly or not at all in mixed lymphocyte culture against HLA-mismatched unrelated stimulator cells. These observations suggest that allogeneic gammadelta(+) T cells could be an effective immunotherapeutic strategy against refractory disease without the risk of graft-versus-host disease.

Allogeneic transplantation across major HLA barriers.

Only one-fourth of patients with fatal haematological disorders and malignancies will have an HLA-matched sibling donor to create access to potentially curative allogeneic stem cell transplantation. Advances in medical management, preparation of the graft and prevention of transplant-related complications, particularly rejection and GVHD, now make it possible to use alternative donors who are not genetically HLA-histocompatible with the patient. Some patients identify unrelated donor options using adult volunteers or cord blood units. All patients have immediate access to one or more genetically half-matched (haplo-identical), HLA partially-mismatched related donors. Using safer non-cytotoxic therapies to ablate the patient's immune system, graft preparation to decrease T-lymphocyte and/or increase CD 34+ cell doses, and post-transplant GVHD and infection prophylaxis, rates >95% for engraftment and <25% for grade II-IV GVHD can be achieved. Thus, disease-free survival rates are comparable to other alternative donors with all outcomes adversely influenced by advanced disease status, poor medical performance and older age.

Epstein-Barr virus-associated B cell lymphoproliferative disorder following mismatched related T cell-depleted bone marrow transplantation.

Epstein-Barr virus (EBV) is closely associated with the progressive and often fatal lymphoproliferative disorders (LPD) in post bone marrow transplantation (BMT) and immunocompromised hosts. The incidence increases significantly when alternative donors or manipulation of marrow graft are used. A total of 318 consecutive BMT from partially mismatched related family donors (PMRD) were performed between February 1993 and June 1998. Known risk factors for the development of EBV-LPD were analyzed which included HLA mismatches, T cell depletion, antithymocyte globulin (ATG), and graft-versus-host disease (GVHD). Eighteen patients (5.7%) developed EBV-LPD at a median of 137 days post BMT (range 48-617). The estimated probability of developing EBV-LPD was 0.13 (95% CI 0.07-0.19) at 5 years. The incidence of grade II to IV GVHD was 19.2%, which translated into an increased trend of EBV-LPD. No correlation with other risk factors was observed. Treatment consisted of supportive antiviral agents, tapering of immunosuppressive regimens, donor leukocyte infusions and radiation. Three patients are alive and disease-free at a median follow-up of 69 months (range 36-71). We observed a lower than expected incidence of EBV-LPD despite existing multiple high-risk factors. We believe prevention and early control of GVHD may contribute to this finding.

Evaluation of the half-life of intravenous human cytomegalovirus immune globulin in patients receiving partially mismatched related donor bone marrow transplantation.

STUDY OBJECTIVE: To evaluate the pharmacokinetics and use of intravenous human cytomegalovirus immune globulin (CytoGam) in allogeneic bone marrow transplantation (BMT). DESIGN: Prospective, nonrandomized, nonblinded, single-center study. SETTING: University teaching hospital. PATIENTS: Five consecutive patients with hematologic malignancies receiving partially mismatched related donor BMT with a uniform conditioning regimen including total body irradiation and chemotherapy. INTERVENTION: Serum immunoglobulin and cytomegalovirus (CMV) titers were measured before and 24 hours after the first CytoGam infusion on day -6 during the conditioning regimen. MEASUREMENTS AND MAIN RESULTS: These levels were measured every 5 days, and a second dose was administered when the CMV titer returned to 25-50% of the 24-hour level. The half-life of CytoGam was approximately 7 days. CONCLUSION: We believe this is the first report of CytoGam's half-life in allogeneic BMT. The information may prove vital in a future study in which the agent's potential beneficial effects can be maximized.

T-cell depletion of bone marrow transplants for leukemia from donors other than HLA-identical siblings: advantage of T-cell antibodies with narrow specificities.

T-cell depletion of donor marrow decreases graft-versus-host disease resulting from transplants from unrelated and human leukocyte antigen (HLA)-mismatched related donors. However, there are diverse strategies for T-cell-depleted transplantation, and it is uncertain whether any improve leukemia-free survival (LFS). To compare strategies for T-cell-depleted alternative donor transplants and to compare T-cell depleted with non-T-cell-depleted transplants, we studied 870 patients with leukemia who received T-cell-depleted transplants from unrelated or HLA-mismatched related donors from 1982 to 1994. Outcomes were compared with those of 998 non-T-cell-depleted transplants. We compared LFS using different strategies for T-cell-depleted transplantation considering T-cell depletion technique, intensity of pretransplant conditioning, and posttransplant immune suppression using proportional hazards regression to adjust for other prognostic variables. Five categories of T-cell depletion techniques were considered: narrow-specificity antibodies, broad-specificity antibodies, Campath antibodies, elutriation, and lectins. Strategies resulting in similar LFS were pooled to compare T-cell-depleted with non-T-cell-depleted transplants. Recipients of transplants T-cell depleted by narrow-specificity antibodies had lower treatment failure risk (higher LFS) than recipients of transplants T-cell depleted by other techniques. Compared with non-T-cell-depleted transplants (5-year probability +/- 95% confidence interval [CI] of LFS, 31% +/- 4%), 5-year LFS was 29% +/- 5% (P = NS) after transplants T-cell depleted by narrow-specificity antibodies and 16% +/- 4% (P <.0001) after transplants T-cell depleted by other techniques. After alternative donor transplantation, T-cell depletion of donor marrow by narrow-specificity antibodies resulted in LFS rates that were higher than those for transplants T-cell depleted using other techniques but similar to those for non-T-cell-depleted transplants. (Blood. 2000;95:3996-4003)

Partially mismatched related-donor bone marrow transplantation for pediatric patients with acute leukemia: younger donors and absence of peripheral blasts improve outcome.

PURPOSE: To extend access to bone marrow transplantation (BMT), we used partially mismatched related donors (PMRD) for pediatric patients with acute leukemia. In this report we sought to determine pretransplantation factors that might predict outcome. PATIENTS AND METHODS: Of 67 such patients, 43 had acute lymphocytic leukemia and 24 had acute myelogenous leukemia. At the time of transplantation, 41 patients were in relapse. Donors included 40 parents, 24 siblings, and three cousins. HLA disparity of two to three major antigens was detected in two thirds of the donor-recipient pairs. Conditioning therapy, including total-body irradiation and chemotherapy followed by graft-versus-host disease (GvHD) prophylaxis with partial T-cell depletion of the graft using T10B9 or OKT3, was combined with posttransplantation immunosuppression. RESULTS: Estimated probability (EP) of engraftment was 0.96 and was not affected by donor-antigen mismatch (AgMM; P =.732). EP of grades 2 to 4 acute GvHD was 0.24 and was not affected by recipient AgMM (P =.796). EP of disease-free survival was 0.26 at 3 years but improved to 0.45 when donors were younger than 30 years (P<.001). EP of relapse at 3 years was 0.41 and reduced with younger donors' age. For patients who were in relapse at the time of transplantation, absence of blasts was associated with a lower relapse rate (0.46 v. 0.84; P =. 083), similar to that of patients in remission. CONCLUSION: PMRD-BMT in pediatric leukemia resulted in high engraftment and low GvHD rates. To improve outcomes, younger donors should be sought, and clinicians should attempt to reduce peripheral blasts in patients who are in relapse.

Comparison of preparative regimens in transplants for children with acute lymphoblastic leukemia.

PURPOSE: Preparative regimens involving total-body irradiation (TBI) produce significant late toxicities in some children who receive bone marrow transplants, including impaired growth and intellectual development. Busulfan is often used as an alternative to TBI, but there are few data regarding its relative efficacy. PATIENTS AND METHODS: We compared outcomes of HLA-identical sibling transplants for acute lymphoblastic leukemia (ALL) in children (< 20 years of age) who received cyclophosphamide plus TBI (CY/TBI) (n = 451) versus those who received busulfan plus cyclophosphamide (Bu/CY) (n = 176) for pretransplant conditioning. Patients received transplants between 1988 and 1995 and their results were reported to the International Bone Marrow Transplant Registry by 144 participating institutions. The CY/TBI and Bu/CY groups did not differ in gender, immune phenotype, leukocyte count at the time of diagnosis, chromosome abnormalities, remission status, or length of initial remission. T-cell depletion was used more frequently in the CY/TBI group; the Bu/CY group included a higher proportion of children who were less than 5 years of age. The median follow-up period was 37 months. RESULTS: The 3-year probabilities of survival were 55% (95% confidence interval [CI], 50% to 60%) with TBI/CY and 40% (95% CI, 32% to 48%) with Bu/CY (univariate P =.003). The 3-year probabilities of leukemia-free survival were 50% (95% CI, 45% to 55%) and 35% (95% CI, 28% to 43%), respectively (univariate P =.005). In a multivariate analysis, the risks of relapse were similar in the two groups (relative risk [RR], 1.30 for Bu/CY v CY/TBI; P =.1). Treatment-related mortality was higher in the Bu/CY group (RR, 1.68; P =.012). Death and treatment failure (relapse or death, inverse of leukemia-free survival) were more frequent in the Bu/CY group (RR, 1. 39; P =.017 for death; RR, 1.42; P =.006 for treatment failure). CONCLUSION: These data indicate superior survival with CY/TBI conditioning, compared with Bu/CY conditioning, for HLA-identical sibling bone marrow transplants in children with ALL.

Non-myeloablative allogeneic transplantation ('microallograft') for refractory myeloma after two preceding autografts: feasibility and efficacy in a patient with active aspergillosis.

A 59-year-old man with a 4-year history of light chain myeloma relapsing after two preceding autografts and salvage therapy with thalidomide underwent a peripheral blood stem cell (PBSC) transplant from his HLA-identical sister after conditioning with 100 mg/m2 melphalan. Graft-versus-host disease (GVHD) prophylaxis comprised cyclosporine. Despite pulmonary infiltrates and sinusitis at the time of the allograft, it was decided to proceed with the transplant because the myeloma was refractory and rapidly progressive. Sputum cultures obtained 2 days before the allograft grew Aspergillus fumigatus 2 days post transplant. A fumigatus grew repeatedly on specimens obtained post transplant. Prompt hematologic recovery was seen with full donor-type chimerism. The fungal infection subsided gradually on a combination of amphotericin B lipid complex and itraconazole. A second aliquot of donor PBSC was infused electively on day +42 to induce graft-versus-myeloma. Complete remission of the myeloma was achieved by 75 days post transplant. No acute GVHD was seen. No chronic GVHD was seen at 16 weeks when he received the third PBSC infusion. He is currently alive and well in remission 9 months post transplant. This case demonstrates the safety and potential usefulness of allogeneic PBSC transplantation with reduced-intensity conditioning in patients with markedly compromised performance status.

Allogeneic transplantation from donors other than HLA-identical siblings.

The decade of the 1990s has witnessed impressive advances in the use of alternative donors for allogeneic transplantations. Through funded collaborative, and single-center research efforts, there is great promise that complete and equal access to allogeneic transplantation will be realized. In the next decade, universal donor availability should maximize the patient's chance of overcoming otherwise fatal disease.

Expression of CD134 (0X-40) on T cells during the first 100 days following allogeneic bone marrow transplantation as a marker for lymphocyte activation and therapy-resistant graft-versus-host disease.

CD134 (OX-40) is an activation-associated antigen which functions as a costimulatory receptor for CD4+ T cells. In order to determine the expression of CD134 during immune recovery following allogeneic bone marrow transplantation (BMT), we measured its expression on T cells and T cell subsets during the first 100 days following BMT in 26 patients. CD4+CD134+ T could be seen approximately 14 days following BMT cells in patients who did not develop GvHD which required therapy (n = 20). The percentage of CD4+CD134+ cells continued to increase up to the fourth week following BMT to a maximum of 40-50% of CD4+ T cells (normal = 1-8%). Two patients who developed Grade I-II GvHD and who responded to treatment with pulsed high-dose methylprednisolone (MPD) showed a decline of approximately 40% in CD4+CD134+ T cells was seen within 48 hours of treatment. Four patients who developed GvHD that was not responsive to MPD and who later developed high IV GvHD showed increasing CD4+CD134+ T cells up to 85% of the CD4+ T cells. Additionally, rapid increases in CD134+ T cells following antibody-based T cell therapy were associated with GvHD recurrence. In no cases was the percentage of CD134+ CD4+ T cells predictive of clinical GvHD. In this exploratory study, we have shown that CD134, although not predictive of the initial onset of GvHD, may be a useful tool for monitoring the response to early GvHD therapy and identification of patients at risk for reemergence of GvHD who may benefit from anti-T cell therapy. Cytometry (Comm. Clin. Cytometry) 38: 238-243, 1999.

Long-term survival and late deaths after allogeneic bone marrow transplantation. Late Effects Working Committee of the International Bone Marrow Transplant Registry.

BACKGROUND AND METHODS: It is uncertain whether mortality rates among patients who have undergone bone marrow transplantation return to the level of the mortality rates of the general population. We analyzed the characteristics of 6691 patients listed in the International Bone Marrow Transplant Registry. All the patients were free of their original disease two years after allogeneic bone marrow transplantation. Mortality rates in this cohort were compared with those of an age-, sex-, and nationality-matched general population. Cox proportional-hazards regression was used to identify risk factors for death more than two years after transplantation (late death). RESULTS: Among patients who were free of disease two years after transplantation, the probability of living for five more years was 89 percent (95 percent confidence interval, 88 to 90 percent). Among patients who underwent transplantation for aplastic anemia, the risk of death by the sixth year after transplantation did not differ significantly from that of a normal population. Mortality remained significantly higher than normal throughout the study among patients who underwent transplantation for acute lymphoblastic leukemia or chronic myelogenous leukemia and through the ninth year among those who underwent transplantation for acute myelogenous leukemia. Recurrent leukemia was the chief cause of death among patients who received a transplant for leukemia, whereas chronic graft-versus-host disease was the chief cause among those who received a transplant for aplastic anemia. Advanced, long-standing disease before transplantation and active chronic graft-versus-host disease were important risk factors for late death. CONCLUSIONS: In patients who receive an allogeneic bone marrow transplant as treatment for acute myelogenous or lymphoblastic leukemia, chronic myelogenous leukemia, or aplastic anemia and who are free of their original disease two years later, the disease is probably cured. However, for many years after transplantation, the mortality among these patients is higher than that in a normal population.